A flogo (for 'floating logo' ) or foam balloon, is a shaped mass of lighter-than-air soap bubbles. They are not balloons, as they have no envelope, but consist merely of a raft of soap bubbles filled with helium. They are shaped by being moulded repeatedly from the launching machine.
It is possible to create foam balloons with diameter of more than 1 metre. Identical foam balloons can be manufactured with the same machine in short repetition periods. Foam balloons are used frequently for advertising purposes, since they can be manufactured easily in the form of company symbols. In principle also wind conditions in the lower atmosphere can be easily monitored with their aid. Foam balloons are not long-term stable, but decay after some hours. Nevertheless, they can reach heights of several kilometres.